Another possible symptom:
katello> system packages --org SimpleOrg --uuid 6dc60321-4427-40d4-8857-0337c6b00a59 --install emacs
Found ambiguous Systems [ 6dc60321-4427-40d4-8857-0337c6b00a59 ] in Org [ SimpleOrg ]
I had talked to Apurva about this yesterday and it seems that this only manifests if there are more than 2 systems in the organization.

Justin, can you help determine why the API call:
/katello//api/organizations/DemoOrg/systems?uuid=f9889fa4-ca52-422b-b8c9-044d82759173
is not filtering on that UUID? For me it returns multiple results even when it should only find one.